1. Field of the Invention
The present invention generally relates to a hot-fillable, blow molded plastic container. More particularly, the invention relates to containers of the above variety having a novel construction and also having panel sections resisting undesirable deformation in accommodating reductions in product volume during cooling of a hot-filled product.
2. Description of the Prior Art
Hot-fillable plastic containers have become commonplace for the package of products (e.g., juices) which must be filled into the container while hot to provide for adequate sterilization. During filling, the product is typically dispensed into the container while at a temperature of 180° F. and above. Such a container is known as a “hot-fill” container. After filling, the container is sealed or capped and, as the product cools, a negative internal pressure forms within the sealed container. If not properly designed, the negative internal pressure will cause the container to deform in unacceptable ways, both from an aesthetic and a performance perspective.
Biaxially-oriented polyethylene terephthalate (PET) containers have long been used to receive the hot-filled product with a resulting minimal amount of distortion in the container after cooling. To accommodate the shrinkage and negative internal pressure, the most often employed method is the incorporation of a plurality of recessed vacuum panels into the body portion of the container. The vacuum panels are designed so that as the product cools, they will deform and move inwardly. In one style of container having vacuum panels, the vacuum panels are equidistantly spaced around the body of the container and separated by land portions. A wrap around label is then used to cover all of the vacuum panels and provide the container with an aesthetically pleasing look.
A major problem with containers of the above mentioned vacuum panel design is that they are not easily handled by the end consumer, particularly in 48 oz., 64 oz. and larger varieties.
Plastic containers having specifically designed gripping areas, hereinafter referred to as pinch-grips, were originally seen in containers for “cold-fill” applications. Not being specifically designed for receiving a hot-fill product, those containers, which did not include vacuum panels, could not accommodate the hot-filling procedure or the decrease in internal pressure which occurs in a hot-fill application.
U.S. Pat. Nos. 5,141,120 and 5,141,121, both to Brown et al., are believed to be the first patents which disclose vacuum panels and pinch-grips in combination in a hot-fill container. More particularly, these patents illustrate and describe the incorporation of the vacuum panels and the pinch-grips together into a common vacuum/pinch-grip panel of the container.
Since the issuance of the Brown et al. patents, other containers have also adopted the vacuum/pinch-grip panel construction. Examples of such patents include U.S. Design Pat. No. 334,457 and U.S. Pat. Nos. 5,392,937; 5,472,105 and 5,598,941.
By combining the pinch-grips and vacuum panels into a common panel as done in the above referenced patents, front and rear label areas can be provided in such a manner that eliminates the need for vacuum panels beneath the label. Instead, horizontal stiffening ribs are provided in these label panel areas for reinforcement and distortion resistance.
When properly designed, vacuum panels of all varieties move inwardly as the container's internal pressure decreases and the product cools. As with all PET or other plastic containers, it is desirable to minimize the weight of the container in order to reduce the material cost in forming the container as well as the shipping costs associated with the container. Because of the vacuum applied to these containers and the need to control distortion of the container under vacuum, weight reduction is increasingly hard to achieve.
Another variety of container is the squeezable container used to dispense a product such as margarine, catsup, lotion, creams or even liquid beverages. A problem associated with containers of this variety is the inconsistent delivery of the amount of product. The amount of product delivered is controlled by the user of the container depending on how much they squeeze the container. While in theory there is a maximum amount of product which can be delivered from a container with one squeeze, these containers are not designed to deliver a preset amount of product per squeeze.
In view of the above and other limitations, one object of the present invention is to provide a lightweight plastic container which resists deformation and distortion during filling, cooling and subsequent handling of the container, which can be easily handled by an end consumer.
Another object of the present invention is to provide a plastic container having a vacuum panel structure which resists undesired deformation and distortion during filling and subsequent cooling, and which absorbs a majority of the vacuum pressure applied to the container.
A further object of this invention is to provide a squeezable container.
Still another object of this invention is to provide a squeezable container wherein a controlled amount of product is dispensed per squeeze.